Generally, a refrigerator has a plurality of storage compartments that can accommodate stored goods and keep food refrigerated or frozen. Additionally, one surface of each of the storage compartments is formed to be opened, such that the food can be put in or taken out therethrough. The plurality of storage compartments may include a freezer compartment in which the food is kept frozen and a refrigerator compartment in which the food is kept refrigerated.
A refrigeration system in which a refrigerant is circulated is typically provided in the refrigerator. The refrigeration system may include a compressor, a condenser, an expander, and an evaporator. The evaporator may include a first evaporator installed at a side of the refrigerator compartment and a second evaporator installed at a side of the freezer compartment. Cooling air stored in the refrigerator compartment can be cooled while passing through the first evaporator, and then supplied again into the refrigerator compartment. Furthermore, cooling air stored in the freezer compartment can be cooled while passing through the second evaporator, and then supplied again into the freezer compartment.
In some cases, a refrigerator may further include a defrosting heater that is provided to remove frost formed on the evaporator. When an amount of the frost formed on the evaporator is increased, there may be a problem that heat exchange efficiency of the evaporator may be lowered. Therefore, when it is recognized that the amount of the frost formed on the evaporator is increased, the defrosting heater can be driven to perform a defrosting operation. When the defrosting operation is performed, a predetermined calorific value may be provided to the evaporator, and thus the frost formed on the evaporator may be removed. In some cases, the defrosting time may be determined by detecting a surface temperature of an evaporator before operating the defrosting heater.